• 한국세라믹학회지
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• 제47권4호
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• pp.329-332
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• 2010

In order to investigate the effect of tail state on the electrical and the optical properties in amorphous IGZO(a-IGZO), a-IGZO films were deposited at room temperature on fused silica substrats using pulsed laser deposition method. The laser pulse energy was used as the processing parameter. In-situ post annealing was carried out at $150^{\circ}C$ right after the film deposition. The $O_2$ partial pressure during the deposition and the post annealing was fixed to 10mTorr. The carrier mobility of the a-IGZO films had a range from 2 to $18\;cm^2/Vs$ at carrier concentrations greater than $10^{18}\;cm^{-3}$. As the laser energy density increased, the Hall mobility increased. And post annealing improved the Hall mobility, as well. The optical property was examined using the ultraviolet-visible spectroscopy. The a-IGZO films that have low Hall mobility exhibited stronger and broader absorption tails in >3.0 eV region. Post annealing reduced the intensity of the tail-like absorption. The absorption tail in a-IGZO films is an important factor which affects the electrical and the optical properties.

• 전자공학회논문지A
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• 제31A권7호
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• pp.85-94
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• 1994

A high-resolution transmission electron microscopy study of the solid phase crystallization of the amorphous silicon thin films, deposited on SiOS12T at 52$0^{\circ}C$ by low pressure chemical vapor deposition and annealed at 55$0^{\circ}C$ in a dry N$_{2}$ ambient was carried out so that the arrangement of atoms in the crystalline silicon and at the amorphous/crystalline interface of the growing grains could be understood on an atomic level. Results show that circular crystalline silicon nuclei have formed and then the grains grow to an elliptical or dendritic shape. In the interior of all the grains many twins whose{111} coherent boundaries are parallel to the long axes of the grains are observed. From this result, it is concluded that the twins enhance the preferential grain growth in the <112> direction along {111} twin planes. In addition to the twins. many defect such as intrinsic stacking faults, extrinsic stacking faults, and Shockley partial dislocations, which can be formed by the errors in the stacking sequence or by the dissociation of the perfect dislocation are found in the silicon grain. But neither frank partial dislocations which can be formed by the condensation of excess silicon atoms or vacancies and can form stacking fault nor perfect dislocations which can be formed by the plastic deformation are observed. So it is concluded that most defects in the silicon grain are formed by the errors in the stacking sequence during the crystallization process of the amorphous silicon thin films.

• Progress in Superconductivity
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• 제9권1호
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• pp.102-106
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• 2007

YBCO films have been synthesized using a spray pyrolysis method. We used nitrates of Y, Ba, Cu as precursors. Deposition was made on $LaAlO_3$ (100) single crystal substrate by spraying the mist of aqueous precursor solution generated by a concentric nozzle. The distance between concentric nozzle and substrate was 15 cm. C-axis oriented films were obtained at deposition temperature of $740{\sim}800^{\circ}C$ and working pressure of 20 Torr. Oxygen partial pressure was 3 Torr and substrate was transported with the speed ranging from 0.23 cm/min to 0.7 cm/min by reel to reel. Scanning electron microscope (SEM) and X-ray diffraction (XRD) observation revealed that films are smooth and highly textured with (001) planes parallel to substrate. Highest critical current density (Jc) was $1.38\;MA/cm^2$ at 77K and self-field for the film with a thickness of $0.5\;{\mu}m$ prepared at a substrate temperature of $780^{\circ}C$ and $PO_2\;=3\;Torr$. The effect of temperature on the microstructure and YBCO phase formation will be discussed.

• Clinical and Experimental Pediatrics
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• 제46권8호
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• pp.777-783
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• 2003

목 적 : E. coli 패혈성 폐가 유도된 신생자돈에서 Nitric oxide(NO) 가스 흡입요법이 혈역학, 가스교환 및 폐 염증 소견에 미치는 영향을 알아보고자 본 연구를 실시하였다. 방 법 : 23마리의 신생자돈에서 도관 삽입과 기도 삽관을 시행하여 기계적 가스 인공환기를 시키면서 CON군(n=6)은 생리적 식염수 5 mL, PCON(n=9) 및 PNO(n=8) 군은 Escherichia coli strain $69{\times}10^9cfu$(10 mL)를 투여한 후 time-cycled pressure-limited 인공환기기로 PIP 30 $cmH_2O$, 호흡수 분당 30회, $FiO_2$ 1.0, PEEP 4 $cmH_2O$의 설정에서 6시간 동안 유지하였다. PNO군에서는 NO 10 ppm을 E. coli 투여 후부터 실험 종료 시까지 기도 내로 투여하였다. 모든 신생자돈에서 가스교환, 혈역학, 폐기능 지수들을 1시간 간격으로 측정하였고 실험 종료후 폐 조직을 얻어 염증반응 정도 지표인 myeloperoxidase 활성을 측정하였다. 결 과 : E. coli가 기도 내로 투여된 PCON 및 PNO군 모두에서 실험 종료시 E. coli 패혈증이 발생하였다. PCON군에서는 시간에 따라 진행되는 폐동맥 고혈압, 저산소혈증, 고탄산혈증, 및 폐 내 단락과 폐 내 사강의 비율의 증가를 보였고 대조군에서는 실험 종료시까지 의미 있는 변화를 보이지 않았다. NO가 투여된 PNO군에서 폐동맥 고혈압이 감소되지 않았으나 폐 내 단락의 의미 있는 개선과 폐 내 사강 비율 증가의 일부 감소에 기인한 저산소혈증 진행의 완화가 관찰되었다. 폐 염증정도의 지표인 폐조직의 myeloperoxidase 활성도는 PCON군에서 CON군에 비해 의미 있게 증가되었으며 이는 PNO군에서 의미 있게 완화되었다. 결 론 : E. coli 패혈성 폐가 유도된 신생자돈에서 NO 가스 흡입요법은 폐 내 단락 개선을 통해 산소화를 향상시켰으며 또한 폐 염증 소견을 완화시켰다.

• Near Infrared Analysis
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• 제2권1호
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• pp.43-53
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• 2001

A non-invasive spectroscopic method is presented for the measurement of pulmonary edema. Both early diagnosis and quantitative edema estimates were investigated. The spectroscopic determination of pulmonary edema involved the acquisition of diffuse reflectance spectra in the near-infrared (NIR) region with change in water concentration - water is the main constituent of edema fluid. Pulmonary edema was induced into the excised perfused lungs of seven animals by elevating the hydrostatic pressure. Estimates of edema were ascertained from a partial least squares regression of the measured spectral response. Actual edema was determined from the change (increase) in total lung weight. Estimates in relative lung weight increases due to in vitro edema were made with the near infrared spectra. The results revealed that fluid accumulation produced spectral changes in the O-H and C-H absorptions as well as scattering changes in the spectra. Histology of the lung was used to verify the presence or absence of interstitial and alveolar edema. Results demonstrated that near infrared spectroscopy might provide a new tool for clinical assessment of pulmonary edema.

• 한국전기전자재료학회논문지
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• 제18권3호
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• pp.253-258
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• 2005

This paper presents characteristics of CrOx thin-film, which were deposited on $Al_2$O$_3$ wafer by DC reactive magnetron sputtering in an argon-oxide atmosphere for high temperature applications. The present paper deals with a study of the technological characteristics of thin film resistors to provide a control in obtaining temperature coefficients of resistance of given value. The optimized condition of CrOx thin-film were thickness range of 2500 $\AA$ and annealing condition(350 $^{\circ}C$, 1 hr) in oxide partial pressure(3.5${\times}$10$^{-4}$ torr). Under optimum conditions, the CrOx thin-films is obtained a high resistivity, p=340 $\mu$Ωcm, a low temperature coefficient of resistance, TCR=-55 ppm/$^{\circ}C$. The CrOx thin films resistors which were fabricated in this paper had excellent characteristics as high precision resistors.

• 제어로봇시스템학회논문지
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• 제14권4호
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• pp.336-341
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• 2008

Recently, research on a flat panel display(FPD) has focused on organic light-emitting display(OLED) which has wide angle of view, high contrast ratio and low power consumption. ITO(Indium-Tin-Oxide) films are the most widely used material as a transparent electrode of OLED and also in many other display devices like LCD or PDP. The performance and efficiency of OLED is related to the surface condition of ITO coated glass substrate. The typical surface defect of glass substrate is measured for electric characteristics and physical condition for transmittance and roughness. Since ITO coated glass substrate can be destroyed for inspection about surface roughness, sheet resistance, film thickness and transmittance, precise fabrication condition should be made based on the estimated relationship. In this paper, ITO films were prepared on the commercial glass substrate by the Ion-Plating method changing the partial pressure of gas(Ar, 02) and the chamber temperature between $200^{\circ}C$ and $300^{\circ}C$. The characteristics of films were examined by the 4-point probe, supersonic thickness measurement, transmittance measurement and AFM. We estimated the relationship between processing parameters(Ar gas, O2 gas, Temperature) and properties of ITO films (Sheet Resistance, Film Thickness, Transmittance, Surface Roughness).

• Journal of Advanced Marine Engineering and Technology
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• 제33권3호
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• pp.373-377
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• 2009

It is well known that SOx and NOx concentration has a considerable influence on the $N_2O$ emission of the greenhouse gas properties. The quantity of SOx generated during combustion, on fuel specific basis, is directly related to the sulfur content of the fuel oil. However, restricting the fuel oil sulfur content is only a partial response to limiting the overall quantity of SOx emissions, as there remains no over control on the fuel oil consumption other than the commercial pressure which have always directed the attention. This study was carried out as a new basic experiment method of emission control, manly targeted to the vessel. In the experiment, where the scrubbing was achieved through spray tower with high alkaline water made from the electrolysis of seawater, the combined action was to neutralize the exhaust gases (SOx, PM, CO etc.), dilute it, and wash it out. The results showed that SOx reduction of around 95 percent or over could be achieved when using in the high alkaline water, and also leaded to a reduction in the stability of the each pollutant components including the PM (Particulate Matter). The results suggest that the seawater electrolysis method has a very effective reduction of emissions without heavy cost, or catalysts particularly on board.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1411-1413
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• 1997

The thin film that is electrically conductive and optically transparent is called conductive transparent thin film. ITO(Indium-Tin Oxide) which is a kind of conductive transparent thin film has been widely used in solar cell, transparent electrical heater, selective optical filter, FDP(Flat Display Panel) such as LCD (Liquid Crystal Display), PDP(Plasma Display Panel) and so on. Especially in PDP, ITO films is used as a transparent electrode in order to maintain discharge and decrease consumption power through the improvement of cell structure. In this study, we prepared ITO by reactive r.f. sputtering with indium-tin(Sn wt 10%) alloy target instead of indium-tin oxide target. The ITO films deposited at low temperature $150^{\circ}C$ and 8% $O_2$ partial pressure showed about $3.6{\Omega}/{\square}$. At the end of firing, the resistance of ITO was decreased, the optical transparence was improved above 90%.

• 한국표면공학회지
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• 제49권6호
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• pp.498-506
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• 2016

Electrochemical measurement using a LSCF6428 electrode was performed to estimate the oxygen potential gradient in the electrode layer and a long time stability test was performed by applied potential to learn the overpotential effect on the LSCF6428 electrode. By fitting the observed impedance spectra, it was obtained that the amount of faradic current decreased with distance from cathode/electrolyte interface. Oxygen potential gradient was estimated to occur within 1 um region from the cathode/electrolyte interface at an oxygen partial pressure of 10-1 bar. The segregation of cation rich phases in the LSCF6428 electrode suggests that kinetic decomposition took place. However, impedance response after applying the potential showed no changes in the electrode compared with before applying potential. The obtained results suggest that segregation of a secondary phase in a LSCF6428 cathode is not related to performance degradation for solid oxide fuel cells (SOFCs).